Chapter. Phytochemicals: The Other Food Components. Images shutterstock.com

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2 14 Chapter Phytochemicals: The Other Food Components Images shutterstock.com

3 Objectives List at least eight groups of phytochemicals and give a food source for each group. Identify possible links between phytochemicals and disease prevention. Describe ways in which food processing can affect the phytochemicals in foods. Plan menus that are rich in phytochemicals.

4 Phytochemicals Phytochemicals are a group of compounds originally produced by plants These compounds help plants resist disease, pests, and extreme weather are found naturally in vegetables, fruits, grains, herbs, and spices give foods their colors and flavors

5 Phytochemical Families: Allyl Sulfides Allyl sulfides are a group of compounds that contain sulfur and increase enzyme reactions These sulfides may kill bacteria, fungi, and viruses are involved in enzyme reactions that rid the body of cancer-causing carcinogens are found in onions, garlic, leeks, and chives

6 Phytochemical Families: Carotenoids Carotenoids act as antioxidants, changing harmful free radicals into harmless compounds Many are used as precursors for vitamin A They usually have a 40-carbon chain with a ring shape at either end Carotenoids are fat soluble continued

7 Phytochemical Families: Carotenoids Carotenoids appear to reduce tissue damage that can lead to cancer cell formation enhance the immune system maintain healthy eye tissue and reduce the risk of age-related eye diseases The 2 subgroups are carotenes xanthophylls

8 Carotenes Alpha-carotene is in pumpkins and carrots Beta-carotene is found in dark green and yellow vegetables Beta-cryptoxanthin is in papayas, oranges, and tangerines Lycopene may reduce prostate cancer and is found in tomato products, watermelon, guava, and red peppers is not destroyed during cooking

9 Xanthophylls These compounds have a hydroxyl group Lutein and zeaxanthin may help eyes filter out harmful blue light They are found in dark leafy greens Elena Elisseeva/Shutterstock.com

10 Phytochemical Families: Flavonoids Flavonoids are responsible for the flavor characteristics of foods They may help fight cancer and reduce the risk of heart disease and stroke Quercetin has antifungal, anti-inflammatory, antiviral, and antibacterial properties They are found in dark chocolate, apples, blueberries, red onions, cranberries, and tea

11 Isoflavonoids Isoflavones are a subgroup of flavonoids found mainly in soy products and legumes They have a hexagonal carbon ring structure The are also called phytoestrogens, or plant hormones Licorice, chickpeas, Chinese cabbage, bok choy, and many processed foods are sources

12 Phytochemical Families: Indoles Indoles are found in large amounts in broccoli, cabbage, kale, and cauliflower, the cruciferous vegetables The indoles stimulate many enzymatic reactions such as the breakdown of estrogen become more available when vegetables are cooked

13 Isothiocyanates Isothiocyanates are a subgroup of indoles that protect against cancer by affecting enzyme reactions are found in cruciferous vegetables are the source for the aromas in Brussel sprouts, cabbage, turnips, mustard greens, watercress, and radishes

14 Phytochemical Families: Phenolic Acids Phenolic acids or phenols are weak organic acids that have a hydroxyl group attached to an aromatic ring Ellagic acid has been found to reduce damage to lungs from tobacco smoke and pollution Berries, citrus fruits, tomatoes, carrots, whole grains, and nuts are sources continued

Phytochemical Families: Phenolic Acids Polyphenols are phenolic acids with more than one carbon ring This phytochemical family may reduce risk of

15 Phytochemical Families: Phenolic Acids Polyphenols are phenolic acids with more than one carbon ring This phytochemical family may reduce risk of some cancers and heart disease They are found in tea, grape products, barley, rosemary, sunflower seeds, and apples Sherri R. Camp/Shutterstock.com

16 Phytochemical Families: Saponins Saponins are molecules formed from a sugar reacting with an alcohol This phytochemical family appears to block DNA reproduction in cancer cells by interfering with enzyme reactions forms a soapy foam with a bitter taste is in spinach, potatoes, tomatoes, beans, soybeans, sugar beets, and legumes

17 Phytochemical Families: Terpenes Terpenes are responsible for the flavors of citrus fruits and many herbs and seasonings They appear to block the formation of cancer cells and the development of tumors Terpenes are in citrus peel (zest) and cherries Best known is taxol, which can be produced in a laboratory and is used to treat ovarian cancer

18 Phytochemicals: Maintaining Food Colors Carotenoids are responsible for yellow, orange, and red pigments in fruits and vegetables When carotenoids are present with chlorophyll, a green color is visible Carotenoids may become isomers when they change in chemical structure, but remain the same compound continued

19 Phytochemicals: Maintaining Food Colors Lycopene gives tomatoes their red color It reduces the risk of cancers in reproductive tissue, enhances the immune system, and slows the aging process of certain body tissues Flavonoids in red cabbage change color as acids evaporate during cooking Vinegar is therefore added to many recipes continued

20 Phytochemicals: Maintaining Food Colors Flavonoids change color in the presence of iron or tin Foods high in flavonoids should be stored in glass, plastic, or stainless steel containers Tea turns cloudy when flavonoids bind with minerals in hard water An acid such as lemon juice is added to dissolve these compounds

21 Phytochemicals: Maintaining Food Flavors Allyl sulfides are released when onions or garlic are chopped Cooking results in a milder flavor Isothiocyanate flavor compounds in Brussels sprouts and cabbage strengthen after cooking The astringency of polyphenols affects the flavor of tea, grape juice, and wines continued

22 Phytochemicals: Maintaining Food Flavors Tannins are polyphenols that cloud liquids, especially beer and apple juice Adding gelatin makes the tannins settle faster for filtering Yeko Photo Studio/Shutterstock.com continued

23 Preserving Phytochemicals Fresh produce has a lower phytochemical content if picked before ripening Ways to maximize phytochemical content include rapid freezing after harvest developing new breeds of plants that form phytochemicals before harvest continued

24 Preserving Phytochemicals Additional research is needed to develop produce with delayed spoiling characteristics determine the impact of oxygen, acids, salts, light, and heat on each phytochemical develop processing methods that maintain and increase phytochemical levels in food

25 Potential Health Benefits of Phytochemicals Research suggests that phytochemicals stop development and/or growth of cancer cells protect cell s genetic material have antibacterial, antifungal, anti-inflammatory, and antiviral properties help the body fight off colds, influenza, and infections reduce the risk of heart disease

26 Increasing Phytochemicals in Your Diet Nutrition powerhouses include broccoli, cabbage, cauliflower, and kale dark green vegetables such as spinach, watercress, collard greens, and parsley white, green, and black tea red and purple grapes or grape juice garlic, onions, leeks, and chives citrus fruits and tomatoes continued

27 Increasing Phytochemicals in Your Diet The Dietary Guidelines recommend teens on a 2,000 kilocalorie per day eating plan consume 2 cups of fruit and 2½ cups of vegetables daily Add phytochemicals to your diet by adding extra veggies to pizza and sandwiches drinking tea with lemon instead of soda choosing fruit for dessert instead of ice cream

28 New Directions for Food Science Functional foods are food products with ingredients that are modified to provide health benefits beyond their traditional nutrients These foods contain bioactive components such as phytochemicals Examples include cholesterol-free eggs, calciumenriched orange juice, and lycopene-rich tomatoes continued

29 New Directions for Food Science Food-specific health claims can appear on product labels if the claims are FDA approved Depending on the claim, the food can be categorized as one of the following regular food, food additive, dietary supplement, drug, medical food, or a food for special dietary use

30 Recap Phytochemicals are found in plants The phytochemical families based on chemical structure are allyl sulfides, carotenoids, flavonoids, indoles, phenolic acids, saponins, and terpenes Phytochemicals may help fight various types of cancer, heart disease, agerelated eye diseases, and others continued

31 Recap Phytochemicals may be impacted during food processing by factors such as the presence of an acid or base freezing or cooking use of certain metals for storage or cooking mechanically altering the food as in cutting or chopping continued

32 Recap Foods highest in phytochemicals include soy products broccoli and dark leafy greens tea red and purple grapes onions, garlic, and chives citrus fruits tomatoes

A FULL SPECTRUM OF NUTRIENTS

A FULL SPECTRUM OF NUTRIENTS All of us remember being told by our parents Eat your Vegetables. They re good for you. Fruits and vegetables are good for our Budgies too. Each color group has its own nutritional